Good Morning Dr.Andrew Rynne. Ahm.im Feel Paranoid About Getting Pregnant

good morning Dr.Andrew Rynne. ahm.im feel paranoid about getting pregnant but the p-test is negative actually i take a 3 p-test and see whats the result all about but the result is negative.we didn't use any protection but we have a birth control for example withdrawal. can i possibly get pregnant if the results is negative and withdrawal or something?